5. How we’re approached and our desire to be consistent affect our decisions.

If I asked you to volunteer for an “Experiment at 7AM,” would you do it? What about a “7AM experiment”? 56% of people asked to volunteer for the first did so, but only 24% volunteered for a “7AM experiment”—fewer people want to wake up early, so the ordering of the words matters. In another experiment, some participants were called and asked if they would hypothetically volunteer for the American Cancer Society. When they were contacted a few days later and asked to volunteer, 31% agreed—versus 4% of people who were cold-called and asked to volunteer for the first time.

8. Comparing people to their friends is the most effective way to make them do something.

When an electric company tried to encourage people to save energy at home, telling them “your neighbors are reducing their energy use” led to a 2% reduction in household usage. Telling people “save energy to save money” or “save energy to save the environment” did not decrease, and in some cases increased, energy usage.

10. The more you’re exposed to something, the more you like it—this is called the mere exposure effect, and it works in milliseconds.

Participants shown a foreign word frequently were more likely to say the word had a positive connotation. The most immediate application of this effect is advertising; the more often you’re exposed to a commercial or ad, the more positively you will rate the company. Flashing images that elicit positive or negative emotions for only a few milliseconds subliminally conditions your attitude.

As a product manager, these remind me that I can’t presume to know how users will respond to a product and messaging. Framing and priming are powerful and significant factors. You have to design an experience, then get it in front of customers to observe how it’s perceived and measure how it’s used.

As Steve Blanks says “no facts exist inside the building, only opinions” so you’d better be a little humble with your beliefs – because real people behave in surprising ways.